This distinction is important. Accuphase manufactures a range of both integrated and pre/power amplifiers operating in Class A, units it has always placed above its Class AB designs in its product hierarchy. Until now, the flagship integrated has been the 50 W, Class A, E-800, but with the arrival of the E-5000, it’s all change…
This is the fourth Accuphase amp to have graced Dickinson Towers, my first encounter being with the E-213, over 15 years ago. The intervening years have seen a change in the Accuphase ‘house sound’. Back when I reviewed (and purchased) the E-213, Accuphase was generally perceived as warm yet musically insightful, with sonic qualities that reflected an almost tube-like fluidity and grace. I remember a widely held assumption (at least in the UK) that the Accuphase amps were tube, or at least part-tube designs. That might be down to some confusion with the similarly styled Luxman products, the colour of the chassis, or the belief that the determinedly retro styling implied a similarly retro topology. But whatever the perception, there was seldom any doubt that music played via Accuphase, was beautiful. Not necessarily ‘cuddly’, but with a gentle euphonic glow to accompany the light from those power meters. This was not the whole truth, but it was also not an entirely unfair perception. Unlike so many amps, which use a warm, euphonic character to mask some pretty heinous musical sins, the Accuphase approach brought delicacy, impact and a way with timing that reintroduced me to and showed me a new side of a lot of familiar music.
The presence of the term ‘phase’ in the company’s name is no accident. Accuphase believe that the phase relationships within music are fundamentally important for a credible, meaningful musical experience. Their designs always seek to preserve and clarify those phase relationships. Used with a pair of time-aligned, phase coherent loudspeakers there has always been something magical about these amplifiers’ uncanny ability to communicate the essence of the music. It’s a recipe that once adopted was hard to give up – and easy to undermine, as more than one visiting amplifier or speaker discovered.
Accuphase operates a five-year product cycle and, with the arrival of later models, including the E-380 and E-480, ‘warm and insightful’ morphed into ‘natural and organic’. That generation of amps and CD players brings a keen sense of the human dimension to music-making: they seemed to understand why we make music and knew how to convey that. Subjectively speaking, they were still slightly warmer than a fair few highly-regarded brands, but only in the sense that live music has that warmth. The Accuphase approach doesn’t strip the music of shape, body and harmonics in the pursuit apparent speed or transparency, like many solid-state designs.
Speaking volumes
One possible reason for this change was Accuphase’s development of its ‘AAVA’ (Accuphase Analog Vari-gain Amplifier) volume control technology. Rather than a conventional preamplifier stage, attenuated by a potentiometer or resistor ladder for volume control, Accuphase approaches this from another direction entirely. The incoming music signal is fed to 16 parallel voltage-to-current converting amplifiers. Each is weighted, so the first converts at a ratio of 1/2, the second 1/4, then 1/8, 1/16… to 1/65,536. These are turned on or off by a CPU coupled to the volume control which, depending on its position can theoretically select any of the thousands of possible different, combined values; although in the real world what all those optional steps offer is superior management of the problem. The summation is then fed into a current-to-voltage amplifier which serves as the pre-amp buffer, and which subsequently feeds the power amplifier gain stage. Accuphase argues that there are several advantages to this configuration, which eliminates variable resistors from the signal path:
